Footwear sole comprising a shock-absorbing device

ABSTRACT

The invention relates to a sole for a footwear item. The invention essentially comprises a sock lining ( 1 ), an insole ( 2 ) and an outsole ( 3 ) as well as a shock-absorbing device ( 4 ). The inventive sole is characterised in that the aforementioned shock-absorbing device is an elastically-deformable element or insert ( 4 ) which is inserted into the sole in the form of a moulded body ( 4 ) comprising mutually-spaced tubular pieces ( 4 ′) having one closed end and one open end which is connected to a common base ( 4 ″).

This application is a 317 of PCT/FR04/00324 filed Feb. 12, 2004.

The present invention relates to footwear soles and has for its objectsuch a sole comprising a shock absorbing device.

Soles of this type have the object of providing better walking comfort,the least sensation of fatigue and ensuring shock absorption.

Several solutions exist at present to absorb shock due to contact of thesole with the ground.

A first solution consists in inserting between the different layersconstituting the sole, namely the outsole, the insole and the stockingliner, a layer of shock absorbing material. This embodiment however hasthe drawback of making the footwear heavy and increasing the height ofthe sole, thereby rendering its use less suitable.

Another solution consists in inserting an air cushion into the heel ofthe footwear. This gives rise to the problem of protecting the airchamber. Thus, there is a risk of deflation and loss of effectivenesswhen the user walks on a pointed or sharp object.

Numerous other solutions have been proposed. Thus, FR 2 577 119discloses a footwear sole provided with a device for restitution ofenergy. In this case, the sole comprises a piston slidably mounted in asleeve in the heel and projecting relative to the surface of the heel.However, this embodiment has a major drawback, namely, that the deviceadapted for energy restitution impedes walking, because the walkerfeels, with each step, this device sinking into the heel. Moreover, saiddevice has a very high risk of causing stumbling and falling and is notsuitable for use on un-level or broken ground.

Another solution is provided by U.S. Pat. No. 4,616,431 relating to asport footwear sole, in which are mounted devices for absorbing shocksin the form of discs inserted in cylinders, a piston being mounted ineach of said cylinders to exert a pressure against said discs in theloaded condition, which is to say when the foot rests on the ground.This embodiment is not impressive, because the shock absorption islimited because the discs are superposed and the shock absorptiondepends on the possibility of compressing said discs.

The same is true for devices disclosed DE 29 01 084, FR 2 774 565, U.S.Pat. No. 6,176,025 and EP0 399 332, in which the elements adapted toabsorb shocks have a relatively low capacity for deformation, limitingtheir effectiveness.

French Patent 2 731 597 in the name of the applicant, discloses a shockabsorbing device permitting improving this capacity to absorb shocks, inwhich an insert is mounted in the heel of the sole, this insert beingconstituted by elements in the form of fingers adapted to be compressedduring walking. This embodiment is limited because the fingers arerelatively small and because they are disposed in a fairly dense manner,which does not promote their deformation and hence their capacity forabsorbing shocks. The device according to this document is more forimproving the comfort of the heel than for absorbing shocks.

The present invention has particularly for its object further to improveshock absorption, overcoming the drawbacks mentioned above and toprovide a solution permitting providing a sole comprising a shockabsorbing device, providing important absorption of shocks independentlyof the terrain, and particularly over non-uniform terrains, and whoseinsertion in the sole does not modify the shape of this latter, whichkeeps its effectiveness, even when said device is pierced. Moreover,this device can be used in numerous types of footwear.

To this end, it has for its object a sole for a footwear article,essentially constituted by a sock liner, an insole and an outsole andcomprising at least one shock absorbing device, characterized in thatsaid shock absorbing device is an elastically deformable element,inserted in said sole and in the form of a molded body constituted bytubular members, closed at one end, mutually spaced and connected attheir open end to a common base.

The invention will be better understood from the following description,which relates to a preferred embodiment, given by way of non-limitingexample, and explained with reference to the accompanying schematicdrawings, in which:

FIG. 1 is a longitudinal cross-sectional view of the sole according toone embodiment of the invention, and

FIG. 2 is a simplified bottom plan view of the sole according to anotherembodiment of the invention.

FIG. 1 of the accompanying drawings shows, by way of example, a solewhich is essentially constituted by a sock lining 1, an insole 2 and anoutsole 3 and which comprises at least one shock absorbing device 4.

According to the invention, this shock absorbing device 4 can be anelastically deformable insert or element, inserted in said sole and inthe form of a molded body constituted by tubular members 4′, closed atone end, mutually spaced and connected at their open end to a commonbase 4″.

The elastically deformable insert or element is preferably mounted inthe insole 2. This embodiment of the shock absorbing device 4 as aninsert permits introducing this latter into all soles of footweararticles by simple provision in their sole of a recess adapted toreceive said shock absorbing device 4. This characteristic isadvantageous, because it permits standardizing the production of solesprovided with such devices 4 and thereby promotes the reduction of costof the manufacturer of these soles.

According to one characteristic of the invention, the common base 4″ canhave a peripheral skirt 4′″ delimiting a chamber receiving the closedends of the tubular members 4′. There is thus obtained a shock absorbingdevice having an open cell structure with perfectly directed deformationwhich promotes the stability of the footwear and permits providingabsorption of the shocks in a completely uniform and vertical manner.

According to the invention, the elastically deformable member 4 can bedisposed in a closed flexible receptacle 6 sealed by a cover 7.

The constituent material of said elastically deformable molded body 4can preferably be selected as a function of its shock absorbingproperties.

So as to achieve optimum absorption of shocks, and according to apreferred embodiment of the invention, the flexible receptacle 6 canform a vertical peripheral chamber about the elastically deformablemolded body 4 and said elastically deformable molded body 4 can be incontact with the cover 7 and with the portion of the flexible receptacle6 opposite said cover 7.

This vertical peripheral chamber thus permits improving the shockabsorption because, in addition to deforming during shock, it isseparated from the elastically deformable molded body 4 by a volume intowhich said molded body 4 can entirely and freely deform during a shock,without being hindered by the walls of the flexible receptacle 6, andthus absorb gently the energy of the shock.

The portion of the flexible receptacle 6 opposite the cover 7 canpreferably have a centering and folding device 8 for the elasticallydeformable molded body 4, permitting ensuring the good operation of thisshock absorbing device 4. Thus, the centering and holding device 8 forthe elastically deformable molded body 4 guarantees a stable positioningof said molded body 4 in the flexible receptacle 6 and thereby uniformshock absorption in the molded body 4 and, because of this, theeffectiveness of the shock absorbing device.

According to a characteristic of the invention, the centering andholding device 8 for the elastically deformable molded body 4 canpreferably be present in the form of a central cup, provided in theportion of the flexible receptacle 6 opposite the cover 7 and matchingintimately the shape of the elastically deformable molded body 4 over aportion of its height.

According to a modified embodiment of the invention (not shown), thecentering and holding device 8 for the elastically deformable moldedbody 4, in the portion of the flexible receptacle 6 opposite the cover7, can also be made in the form of a projecting portion penetrating in acentered manner the elastically deformable molded body 4.

According to another embodiment (not shown), the elastically deformablemolded body 4 can be in intimate contact with the interior surface ofthe flexible receptacle 6. In this case, during shock, the flexiblereceptacle 6 does not hinder the deformation of the elasticallydeformable molded body 4 and itself deforms because of its elasticproperties.

According to another characteristic of the invention, the outsole can beprovided with a lower element 9 for protection of the elasticallydeformable receptacle 6, integrated with said outsole by molding. Thiselement 9 ensures the protection of the elastically deformablereceptacle 6 against wear during walking, and also against penetrationof dirt such as rust, water or the like.

As a function of the use of the footwear and of the needs of its user,and according to an embodiment of the invention, at least oneelastically deformable element 4 can preferably be inserted in the heelportion 5 of the sole.

To absorb shocks at the front of the foot, and in according to anembodiment of the invention, at least one elastically deformable element4 can be inserted into the sole, at at least three bearing points 10, 11and 12 forming the support triangle of the front of the foot (see FIG.2).

According to a modified embodiment of the invention (not shown), thereceptable or receptacles 6 can open by their lower face through theoutsole 3. This or these receptacles 6 do not hinder the user duringwalking, because they compress when this latter places the foot on theground, whilst absorbing the shocks. Moreover, such an embodimentpermits obtaining a simplified sole at least cost.

Of course, the invention is not limited to the embodiment described andshown in the accompanying drawings. Modifications remain possible,particularly as to the construction of the various elements or bysubstitution of technical equivalents, without thereby departing fromthe scope of protection of the invention.

1. Sole for a footwear article, essentially constituted by a stockingliner (1), an insole (2) and an outsole (3) and comprising at least oneshock absorbing device (4), in the form of an elastically deformableinsert or element (4), inserted in said sole and in the form of a moldedbody (4) constituted by tubular members (4′) closed at one end, mutuallyspaced and connected at their open end to a common base (4″),characterized in that said common base (4″) has a peripheral skirt (4′″)delimiting a chamber receiving the closed ends of the tubular members(4′), in that the elastically deformable element (4) is disposed in aflexible receptacle (6) closed in a sealed manner by a cover (7) and inthat the outsole (3) is provided with a lower element (9) for protectionof the elastically deformable receptacle (6) integrated with saidoutsole (3) by molding.
 2. Sole for a footwear article, according toclaim 1, characterized in that the flexible receptable (6) forms avertical peripheral chamber about the elastically deformable molded body(4) and in that said elastically deformable molded body (4) is incontact with the cover (7) and with the portion of the flexiblereceptacle (6) opposite said cover (7).
 3. Sole for a footwear article,according to claim 2, characterized in that the portion of the flexiblereceptacle (6) opposite the cover (7) has a centering and holding device(8) for the elastically deformable molded body (4).
 4. Sole for afootwear article, according to claim 3, characterized in that thecentering and holding device (8) for the elastically deformable moldedbody (4) is present in the form of a central cup, provided in theportion of the flexible receptacle (6) opposite the cover (7), andintimately matching the contour of the elastically deformable moldedbody (4) over a portion of its height.
 5. Sole for a footwear article,according to claim 3, characterized in that the centering and holdingdevice (8) for the elastically deformable molded body (4) is provided inthe portion of the flexible receptacle (6) opposite the cover (7) and ispresent in the form of a projecting portion penetrating in a centeredmanner the elastically deformable molded body (4).
 6. Sole for afootwear article, according to claim 2, characterized in that theelastically deformable molded body (4) is in intimate contact with theinternal surface of the flexible receptacle (6).
 7. Sole for a footweararticle, according to claim 1, characterized in that at least oneelastically deformable element (4) is inserted in the heel portion (5)of the sole.
 8. Sole for a footwear article, according to claim 1,characterized in that at least one elastically deformable element (4) isinserted in the sole, at one of three bearing points (10, 11 and 12)forming the support triangle for the front of the foot.
 9. Sole for afootwear article, according to claim 7, characterized in that thereceptacle or receptacles (6) open by their lower surface through theoutsole (3).
 10. Sole for a footwear article, according to claim 8,characterized in that the receptacle or receptacles (6) open by theirlower surface through the outsole (3).